1. Field of the Invention
The present invention relates to an automatic sheet reversing apparatus and, more particularly, to an automatic sheet reversing apparatus which is used for an electrophotographic copying apparatus or a printing apparatus and which reverses a one-side copied sheet and feeds the reversed sheet in the electrophotographic copying apparatus or the printing apparatus so as to obtain a two-side copied sheet.
2. Description of the Prior Art
In conventional automatic sheet reversing apparatuses which are used in electrophotographic copying apparatuses and printing apparatuses and which reverse one-side copied sheets and feed the reversed sheets to obtain two-side copied sheets, a predetermined number of one-side copied sheets are received, and the sheets are then fed such that the trailing ends thereof are fed first in the second copying process. The sheets are conveyed in a paper feeder and then fed to the electrophotographic copying apparatus or the printing apparatus. Conventional automatic paper reversing apparatuses of this type are described in Japanese Patent Disclosure Nos. 59-82247 and 59-114227. In these apparatuses, when one-side copied sheets are reversed and held in a stacker, the stacker is inclined forward, so that the feed direction of the sheets is downward and the leading ends of the sheets abut against the stopper of the stacker, thus sequentially stacking the sheets.
When the sheets are stacked in the manner as described above, however, the sheets are electrostatically charged to interfere smooth feeding. Furthermore, the sheets are conveyed such that an air layer of a predetermined thickness is formed between every two adjacent sheets and disables smooth stacking. When the sheets are charged as described above, the sheets are attracted to adjacent members. In this case, paper jam occurs and smooth feeding cannot be performed.
In the conventional sheet reversing apparatus of this type, if the reversed one-side copied sheets are curled upward when they are stacked in a stacker as an intermediate tray, the two sides of the sheet are curved upward. As a result, the sheets cannot be properly housed in the intermediate tray.
In this case, when a press member is used to press the curled sheet, the member must be placed on side plates for defining the two sides of the sheets or is disposed inside the side plates.
Since the side plates are moved in accordance with paper sizes, however, the conventional press plate must be arranged in accordance with a minimum or maximum paper size and be placed on the side plates upon its inward movement.
For this reason, when the press plate has a minimum paper size, it cannot properly press a maximum size sheet. Similarly, when the press plate has a maximum paper size, it cannot properly press a minimum size sheet, either.